Enhancing Wear Resistance and Adhesion of Primer Coatings on Laser-Textured Milled Carbon Fiber-Filled Basalt Composites

The present study explores the effects of pre-coating on the wear performance of milled carbon fiber-filled basalt composites via laser texturing. Laser texturing was used to change surface topography, enhancing adhesion and wear resistance. Incorporated 0 wt.% and 5 wt.% milled carbon fibers in an epoxy matrix. A fiber laser system was employed for surface treatment, in which power, scanning speed, and pulse frequency were optimized. For pre-coating, an epoxy-based primer was used, and the adhesion and wear performance of the coating was studied using ball-on-disc wear tests. Experimental results demonstrate that laser texturing significantly increases coating adhesion by enhancing the surface roughness and mechanical interlocking. The laser-induced textures displayed mostly square-shaped dimples, reducing practically by around 22% the deformation of the primer coating when used in combination with 5 wt.% carbon fiber milling. The textured surfaces reduced friction noticeably, leading to a decrease of as much as 23% in the coefficient of friction from untreated surfaces. SEM and 3D profilometry analysis indicate that the lower delamination observed in the laser treatment led to optimal coating retention. The original contribution of this work consists of the unique integration of laser surface engineering with pre-coating treatments toward improved tribological performance.